Heya,
You firstly need a license to run unattened. I think it's around $500 p/a. Then you need to setup the machine group and machine. You'll need to authorise the connection on the desktop client on the remote computer.
Once you've setup the machine go back to the flow and tell it to run on the machine unattended.
Notes:
You'll need to keep the verisons of PAD in sync across the developing and running machines
OCR does not seem to work unattended
The computer must be turned on and the user must not be logged in
If you struggle I can write these steps in a bit more detail for you 🙂